Towards better soil management for farms

Farming practices that reduce the amount of carbon in soil can disrupt soil microbial activity, soil structure, and water and nutrient supply to crops. It can also make soil less capable of regulating greenhouse gas emissions.

The EU-funded CATCH-C (Compatibility of agricultural management practices and types of farming in the EU to enhance climate change mitigation and soil health) initiative focused on best management practices (BMPs) to reduce and prevent these problems. The effects of soil management options were identified, as were the barriers to adopting BMPs in different types of farms.

Data from over 300 long-term trials were used to quantify the effects of different soil management options on selected indicators for soil quality, crop productivity and climate change mitigation.

Overall, BMPs did improve soil quality in a number of ways. CATCH-C observed that BMPs often came with trade-offs such as lower yield or increased emissions. Researchers also found that local conditions strongly affected BMP efficiency, and even the direction of impact.

Twenty-four farm types across Europe were selected based on soil and climate data combined with economic farm traits. For these farms, researchers surveyed over 2 500 farmers' perceptions of soil management practices and the concept of soil degradation. The team also reviewed soil-related EU policies and how they promote or discourage the adoption of BMPs.

Researchers analysed policy packages that can affect soils to identify how they include soil stakes, going from the objectives in EU or national documents to local implementation of measures. Overall, the embeddedness of soil stakes into policies was found to be low. Identified key aspects to make policies more effective include: facilitating a more bottom-up incorporation of specific local stakes, mechanisms for sharing research and dissemination cost, monitoring of impacts using sound indicators, and optimizing spatial allocation to best-equipped regions of funds that intend to serve EU-wide public goals (e.g. carbon retention and sequestration).

Finally, CATCH-C created KnowSoil, a web-based decision tool that summarises the costs and benefits of sustainable practices for farmers, the public and the environment. The tool is available in seven languages and provides scientifically validated guidelines for better soil management, around which EU soil policies can be shaped.